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Write the Cofactor of A12 in the Following Matrix ⎡ ⎢ ⎣ 2 − 3 5 6 0 4 1 5 − 7 ⎤ ⎥ ⎦ . - Mathematics

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प्रश्न

Write the cofactor of a12 in the following matrix \[\begin{bmatrix}2 & - 3 & 5 \\ 6 & 0 & 4 \\ 1 & 5 & - 7\end{bmatrix} .\]

उत्तर

\[\text{ Given: }\begin{bmatrix}2 & - 3 & 5 \\ 6 & 0 & 4 \\ 1 & 5 & - 7\end{bmatrix}\] 
Here, 
\[ a_{12} = - 3\] 
\[\text{ Cofactor of }a_{12} = \left( - 1 \right)^{1 + 2} \begin{vmatrix}6 & 4 \\ 1 & - 7\end{vmatrix} = - ( - 42 - 4) = 46\]

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अध्याय 6: Determinants - Exercise 6.6 [पृष्ठ ९१]

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आरडी शर्मा Mathematics [English] Class 12
अध्याय 6 Determinants
Exercise 6.6 | Q 35 | पृष्ठ ९१

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